Abstract: | Ten chemicals were assessed for blastomogenic activity in adult wts/+ heterozygotes of D. melanogaster. All of the strong mammalian carcinogens tested (benzo(a)pyrene (B(a)P), pyrene, aflatoxin B1, 2-acetylaminofluorene (2-AAF) and cis-dichlorodihydroxydiamminoplatinum IV) were also shown to be strong Drosophila blastomogens. They induced several times more tumors than their counterparts that are less carcinogenic for mammals (4-acetylaminofluorene (4-AAF), aflatoxins B2 and G2) and 4-(methylnitrosamino)-1-(-3-pyridine)-1-butanone (NNK). Benzo(e)pyrene (B(e)P) and pyrene demonstrated minor effects. Most tumors were localized on the wing and notum, which are the derivatives of the wing disc. Humeri derived from dorsal prothoracic disc and the abdominal tergites and sternites had the lowest number of tumors. The tumor frequency in the cross of the wild type females with wtsP2/TM6B males was different from that in the reciprocal cross. The former type of cross exhibited consistently higher tumor frequency both in the experimental and control series. |